Ridge, Rake, and Eaves
Most panel suppliers offer standard ridge components for use
with their panels. These come in two varieties. One type has a
formed flange to nest with the panels. While this type is
easier to seal, the installer must keep the panel ribs
perfectly aligned on both sides of the ridge. The other type
has a flat flange that overlays the panels, and a closure strip
is added. With both ridge types, use a sealant tape to seal the
joint between roof panel and ridge cap.
When using long panels that are subject to substantial
thermal movement, make sure the ridge cap and the panels are
fastened separately to the deck.
Rake flashing. Prefabricated rake flashings
are also available from the panel supplier. However, these are
usually too large and "boxy" to use on a residence. Instead,
ask the panel supplier to furnish flat sheet stock with a
matching finish. You can then take the flat material to a local
sheet metal shop, and have it bent into a simple L-flashing, as
shown in Figure 5.
Figure 5.
Rake flashings are
fabricated from flat sheet stock provided by the roof panel
manufacturer. Extend the horizontal leg of the flashing so it
attaches with butyl tape and screws to the roof at a high
rib.
Ideally, this flashing should attach to the roof at a high
rib with sealant, even if this means extending the horizontal
leg a few extra inches. Fasten the rake flashing to the fascia.
This is best done using a metal cleat that matches the angle of
the drip leg. Or, you can fasten through the face of the
flashing with a washered screw.
Eaves flashing. Bend a simple drip edge for
the eaves, as shown in Figure 6.
Figure 6.
When gutters are used,
seal the eaves as if they will be submerged in water. Use
rubber closure strips sealed on all sides with butyl tape to
prevent snow, rain, and vermin from entering the panel voids.
Without gutters, roof panels should overhang the drip edge at
least 4 inches.
This drip flashing should be nailed down just enough to hold
it in place prior to installing the roof panels. When the roof
panels are installed, the screws should pierce the panel, drip
flashing, and deck. Use eaves closures to prevent snow, rain,
and vermin from entering the panel voids. Again, use tape
sealants in conjunction with the closures, especially in severe
climates.
If gutters are used, take extra care when installing tape
sealants and eaves closures. Freezing gutters and ice dams at
eaves can cause serious moisture problems. If you seal the
eaves edges to withstand occasional submersion in water, you'll
never be disappointed or accused of misjudgment. If gutters are
not used, the roof panels should overhang the drip edge by at
least 4 inches.